Added support for the Xbox One gamepad on OSX

Added support for the Xbox One gamepad on OSX

BUG=
R=scottmg@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=253031

[bajones, 2014-02-22 00:06:01]

This is the result of some evening hacking on my part. I'd like to see it get in
because it's a nice gamepad and it's fun that we'd be essentially the only
product that supports it to date.

[scottmg, 2014-02-24 17:37:22]

I don't know Mac, but seems reasonable to me.

Are there any exisiting documentation pages/repos that you can link to in a
comment for background?

LGTM with below.

https://codereview.chromium.org/176003003/diff/1/content/browser/gamepad/xbox...
File content/browser/gamepad/xbox_data_fetcher_mac.cc (right):

https://codereview.chromium.org/176003003/diff/1/content/browser/gamepad/xbox...
content/browser/gamepad/xbox_data_fetcher_mac.cc:173: XboxController::Data*
normalized_data) {
nit; indent

https://codereview.chromium.org/176003003/diff/1/content/browser/gamepad/xbox...
content/browser/gamepad/xbox_data_fetcher_mac.cc:204: XboxController::Data*
normalized_data) {
nit; indent

https://codereview.chromium.org/176003003/diff/1/content/browser/gamepad/xbox...
content/browser/gamepad/xbox_data_fetcher_mac.cc:557: if (length < 2) return;
nit; return on next line

https://codereview.chromium.org/176003003/diff/1/content/browser/gamepad/xbox...
content/browser/gamepad/xbox_data_fetcher_mac.cc:571: return;
does this return ever get hit? does it send partial updates or something?

[bajones, 2014-02-24 17:58:59]

On 2014/02/24 17:37:22, scottmg wrote:
> Are there any exisiting documentation pages/repos that you can link to in a
> comment for background?

Nope, unfortunately Microsoft hasn't released any documentation and the
controller is new enough that there's not a lot of community information. This
is based on my own observation and notes while hacking on the controller and
hex-dumping packets. :)

>
https://codereview.chromium.org/176003003/diff/1/content/browser/gamepad/xbox...
> content/browser/gamepad/xbox_data_fetcher_mac.cc:571: return;
> does this return ever get hit? does it send partial updates or something?

I've never seen it happen, but this keeps the logic consistent with the 360
packet reader code above, and since we're doing a reinterpret cast it's probably
not a bad safety.

[bajones, 2014-02-24 17:59:10]

The CQ bit was checked by bajones@chromium.org

[commit-bot: I haz the power, 2014-02-24 18:01:15]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bajones@chromium.org/176003003/80001

[commit-bot: I haz the power, 2014-02-24 20:24:18]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bajones@chromium.org/176003003/80001

[commit-bot: I haz the power, 2014-02-24 21:07:51]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bajones@chromium.org/176003003/80001

[bajones, 2014-02-24 23:49:42]

Committed patchset #2 manually as r253031 (presubmit successful).